Question 1: What is the scientific definition of momentum?

Answer: Momentum is the product of an object's mass and its velocity, expressed as p = mv.

Question 2: Explain why a small object moving at high speed can have the same momentum as a large object moving slowly.

Answer: Because momentum depends on both mass and velocity; a small object can have high momentum if its velocity is very high, balancing the momentum of a larger object moving slowly.

Question 3: Describe the mechanism by which momentum is conserved during a collision.

Answer: Momentum is conserved during a collision because the total momentum before the collision equals the total momentum after, assuming no external forces act on the system.

Question 1: A car with a mass of 1500 kg is traveling at a velocity of 20 m/s. Calculate its momentum.

Answer: Momentum p = m × v = 1500 kg × 20 m/s = 30,000 kg·m/s

Question 2: A bicycle has a mass of 15 kg and is moving at 10 m/s. What is its momentum?

Answer: p = 15 kg × 10 m/s = 150 kg·m/s

Question 3: If the momentum of a skateboarder is 120 kg·m/s and their mass is 60 kg, what is their velocity?

Answer: v = p / m = 120 kg·m/s / 60 kg = 2 m/s

Question 1: Describe a simple experiment to demonstrate the conservation of momentum using carts on a track.

Answer: Set up two carts on a frictionless track. Push them towards each other with known masses and initial velocities. Record their speeds before and after collision. The total momentum before and after should be equal, demonstrating conservation.

Question 2: Identify two variables you would control in the experiment and two safety precautions you should take.

Answer: Variables to control include the masses of the carts and the initial velocities. Safety precautions include wearing safety goggles and ensuring the track is clear of obstacles.

Question 1: A 500 kg truck moving at 10 m/s collides with a stationary 300 kg car. After the collision, the truck slows to 8 m/s. Assuming momentum is conserved, what is the velocity of the car after the collision?

Answer: Initial total momentum = (500 kg × 10 m/s) + (300 kg × 0) = 5000 kg·m/s. Final total momentum = (500 kg × 8 m/s) + (300 kg × v). Set equal: 5000 = 4000 + 300v. Solving for v: 300v = 1000, v ≈ 3.33 m/s.

Question 2: A ball with a mass of 0.2 kg is thrown at a wall at 15 m/s and bounces back at 10 m/s. Describe what this data suggests about the change in momentum.

Answer: The change in momentum is the difference between the initial and final momentum. Since the velocity reverses direction, the momentum change is Δp = m(v_final - v_initial) = 0.2 kg × (-10 m/s - 15 m/s) = -5 kg·m/s, indicating a 5 kg·m/s decrease in momentum.

Question 1: Explain how understanding momentum helps improve safety features in automobiles, such as airbags and crumple zones.

Answer: Understanding momentum allows engineers to design safety features that increase the time over which a collision occurs, reducing the force experienced by occupants and preventing injuries.

Question 2: Describe how momentum is relevant to sports, such as in a baseball bat hitting a ball or a football player tackling.

Answer: In sports, momentum explains how the force of impact depends on mass and velocity. A heavier or faster-moving object transfers more momentum, affecting the outcome of hits and tackles.